Pitman



June 8 1926. 1,588,138

J. P. NElLsoN, sR

PITMANl Filed May 16, 1925 2 Sheets-Sheet 1 June 8 1926. 1,588,138

J. P. NELSON, sR

PITMAN Filed May 1e, 1925 2` sheets-sheet 2 INI /5 l the wal vpin of a standard drilling'rig for oil wells.

lPatented June 8, 19226. p

1,588,188/ PATENT oFl-lcl-z.;

:LAMES PETTIGREW mansiones., or TULSA, omnom.

PITMAN.

'Application ma :my 16, v1825.- seigial un. 80,751.

My invention relates to a pitman which is especiall suitable for operatively connecting ing beam and' band wheel wrist The principal object of the invention is to provide a simple, rugged and eliclent pitman whose wrist pin bearings may be renewed with a minimum of time and labor and which may be quickly associated with or disengaged from the wrist pin and walk ing beam of the drilling rig as occasion may reuire in the course of drilllng operatlons.

principal feature of the'invention consists 1n forming the pitman with a yoke in which a plurality of relatively movable wrist pin healing members are slidably mounted, spring means being interposed between the yoke and one of the bearing members, and means bein o eratively interposed between the ot er aring member and the yoke-for retaining the pitman in operative relation to the wrist pin of the band-wheel.

A further feature of the invention consists in forming the itman with a yoke within which a plurality of opposed wrist pin beari devices are mounted, andin interposing etween the yoke and one of the bearing devices means movable at will for causing said bearing devices either to be 4brought into operative relation with the wrist pin of the band wheel or to be released therefrom, each of the said bearing devices involving a plurality of detachably connected members between which' portions of the oke are embraced.

Anot er feature of the invention4 consists in mountin within the pitman yoke a plus rality of re atively movable .wrist pin bearing devices adapted to receive the wristpin between them, each of said devices involving a recessed block, a removable wrist pin bearin -member fitting into the recess of said b ook, and means for retaining said block in assembled vrelation to the yoke, and

releasable means being o eratively interposed between the yoke an one of the bearmg devices for actuatin the latter to force it into operative relatlon with the band wheel wrist pin.

still further feature of the inventionY consists in forming the itman with a yoke in which a plurahty o relatively movable wrist pin bearing devices are mounted, and

in providing .toggle means for moving one of said bearing devices with respect to the embodiment of` the invention, t-he scope.

whereof is pointed out in the claims,-

Figure 1 is an elevational .view of a portion of a so-called standard rig for drilling oil wells, illustrating the operative relation of the pitman to the walking beam and to the wrlst pin of the band wheel.

Figure 2 is an elevational view of the wrist pin engaging end of the pitman, the Wrist pin bearings being shown 1n the separated relation occupied by them. when the pitman is being applied to or released from the wrist pin.

VFigure 3 is a sectional view on the line 3 3, Fig. 2, showing a portion of the band wheel wrist pin andillustrating the pitmanv bearings in working relation thereto.

Figure 4 is a detail elevational view ofthe upper or walking beam engaging end of the pltman.

Figure 5 is a detail view artly in elevation and partly in section o the portion of the pitman illustrated in Fig. 4. l

Flgure 6' is a detail sectional view of the lower portion of the pitman, the view being taken in a plane'atvright angles to the axis beam, 2 is the band wheel, and 3 is the banl wheel wrisiilpin ofv-a standard or cable-tools rig commo y employed for drilling oil or other deep wells. The band wheel,which is belt driven from the engine (not shown) operates the walking beam through the .in tervention of a pitman 4 fol-min an' operative connection between said wa ing beamv and the wrist pin 3. The various operations necessary to be performed in sinking a well necessitate frequent disconnection vof the pitman in order that the band wheel 2 may rotate without actuating the walking beaml It 1s therefore advantageous to construct .the pitman in such mannerthat it may be conveniently disconnected with a minimum loss of time, but this desirable result must. be attained without impairingj they eliiciency and reliability of the pitman. in service..

The.v pitman 4 is preferably constructed with an intermediate bar member" toitlie upper end of which. is. secured a stirrup 6. and to the lower end of' which is attached a yoke 7, preterably-bymieans of rivets 8.` They pitman member 5 may7r advantageously' be formed as an eye beam section through. the flanges of. which the rivetsy 8'; extend. The stirrup 6', which constitutes; means for-'f operatively' connecting the pit'man to -thef walking beam, may be: of the well known form employed for this purpose. It. is.I prefs erably secured to the upper end of the pitman bar 5 byk means ofi bolt-S19 which pass' through the web of the said bar" andthrough filler members 10 interposed be:-4

tween the stirrup and the member 5 on opposite sides oi thel web of: the latter; To:-y

allow for increasing or decreasing4 the length of the pitman as mayI bev desired,.thev

filler members 10 which space: the;I stirrup from the web of the bar member 5f arezpro vided with additional boltholes 11 which register with corresponding additional bolt may be interchangeabler an opening 32 is holes 12 in theweb of the'pitman bar.

The yoke 7' is most advantageously formed as an integral steel casting having:

arallel side bars 13 which` are.` rigidlyunited y an` upper tie bar 14 and a lower tie bar 15 spaced from the latter. The lower bar 15 is preferably'formed with a plurality' of spring pockets 16 for receiving the springs. 1

between the yoke and lower wr1sty pin bear ing carried` by said yoke.'1 These springs 'serve to cushion the strains; induced during; an upstroke of the pitman.

Mounted in spacedv relation betweeny the arms of the yoke are a plurality of opposedw'ist in bearing devices 18 which are a a them'. Each of said bearingl devices involves a plurality of detachably connected members embracing the yoke arms 123" soas to 'retain these parts in assembled relation while permitting the bearing devices to be capable of relative movement with respect to each other and to the yoke in which they are mounted. The yoke engagingu members ofthe wrist pin bearing devices are detachably connected. and. preferably comprise, in each instance, a recessed bearing block to which'. a plate member 19 is secured; by

means of bolts 20. The recessedY block 21 of the` upper bearing is. preferably provided with a centrally disposed perforated lug-22 Vto permit the pivotal attachment of toggle means for sliding the upper wrist pin bearing in the yokek as may be `necessary either toy bring the bearings into operative', relation;

to the wrist pin or to release them therel which are preferably interposed to receive the wrist p'in 3 between..

from. The bearingbleekv 21 is` also preferably provided with threadedv recesses 23 for receiving the correspondingly' threaded upper ends: of shouldered stud guide pins 24 serving to maintain the wrist; pin bearing members 25 in. pre-per relation to: the respective recessed blocks' ini wliifclr they' tit. Springs 26 which. respectively encircle the pins 24 and arey interposed between the wrist bearing members 25 operateato force the ybearing members. apart. and maintain them in separated relation whenf. the toggle mechanism is actuated to permit.,y the pitmanto be disengaged froml the? wrist pi'n 3;.

The recessed block 27V of the lower bearing device is provided with.. suitable,7 chambers 28 for receivingl and guiding the pins 24 and is fashionedl asV :it-29 toreceive and provided in each ofthem', said openings being threaded' so thatthe bearing positioned vbelow thel wrist pin ma be held in place by a tap screw 31 which extendsthrough the lower block. 27 ofv the bearing device.

The bearing members 25v which engage they wrist pin are preterably identical in form. in all respects. In the present instance,y and? is? preferred, the; bearing surfaces are curved so as to conform to a wrist pin of thel oval. type. As shown, the recessesf33 with'A whichv the., blocks 21 and 27 are.v respectively provided for receiving the bearing members 25 are shouldered to correspond to saidrbearing members 25 so that the,l latter are effectively maintained against' shifting, Eachfof the members 25 preferably bears wholly against its neighboring block, instead of imposing a portionof the `thrust of the wrist pin on the detachable plate 19 associated with the'. block. To this end the plates 19 are cutaway as indicated at 34 to permit a portion of each ofthe respeetivey blocksY 21 and 27 to intervene between the plates 19 and the bearing members 25 associated therewith.

Thel upper wrist.y pin bearing device 18 is designed toVl be moved: toward and from the opposed bearing device so as to permit the wrist pin to be engaged with and released from said bearing devices at will. The means employed for this purpose constitutes a toggle. mechanism which is interposed between the upper transverse bar 14 ofthe'y yoke; and the adjacent bearing device. It involvesa bent operating lever or handle of a bolt 36 to an integral link 37.

1,5ss,1ss

35 which is pivot-ally connected by means The - l lower end of the link is bifurcated to receive Y as to embrace the lever 35. The upper end of the levery is received between the jaws of a clevis bolt 39 to which it is pivotally attachedby a bolt 40. The upper end of the clevis bolt, which passes through the transverselyl extending bar 14 of the yoke, is threaded for the reception of two nuts 41 which are disposed upon opposite sides of said bar. By this means the toggle mechanism is supported by the yoke in a manner enabling it to be adjusted so as to cause the wrist pin bearing devices to assume proper operative relation to the wrist pin when theV lever 35 is manipulated to move the upper bearing device downwardly in the yoke. As

shown in Fig.v 3, the'construction is such that when the lever 35 is actuated to force the upper bearing member into operative position, the pivot pin 36 passes somewhat beyond the line connecting the pivotal points 38 and 40, thusl enablin the toggle mechanismto operate as a loc for malntaining the bearing devices in operating relation to the wrist pin 3. The position which the lever- 35 assumes when the pit,- man is to be released'v from the wrist pin is illustrated in dotted lines in Fig. 3.

It will be perceived that a pitman involving the invention may be constructed of comparatively few and simple parts, that it may be readily brought into operative relation with the wrist pin and walking beam and as readily disengaged therefrom, and that the renewal of bearings for the wrist pin lmay be effected witlra minimum vof labor and without the destruction of any parts; j

I claim 1 A pitman for operatively connecting the wrist pin and walking beam of a drilling rig, said pitman being provided at one endwith a yoke, and having a plurality of relatively movable wrist pin bearing mem-v bers slidably mounted on said yoke and adapted to receive the wrist pin between them, and embodying spring means inter"` posed between said yoke and one of said bearing members, and also embodying means cooperating with 'the other bearing member and with said yoke for releasably retaining said'last named bearing member in operative rel-ation to Said wrist pin.

2. A pitman for o eratively connecting the wrist pin and wa ing beam of a drilling rig, said pitman embodying a yoke, a plurality of opposed wrist pin bearing devices mounted within said yoke and adapted to receive the wrist pin between them, and

movable means operatively interposed be-k tween said oke and one Yot said bearing de-y vices for eldcting relative movement of said' bearing devices permitting said wrist pin to be engaged with and released from said bearing devices at will, said movable means when in one position .serving to maintain one of said bearing devices in operative relation to the wrist pin, and .each of said i bearing devices involving a plurality of detachably connected` members embracing portions of saidyoke between them.

3. A pitman for operatively connecting the wrist pin and walking beam of a drilling rig, said pitman embodying a yoke having spaced arms and a pluralty of spaced bars integrally connecting said arms, a plurality of opposed relatively movable wrist pin bearing devices mounted between said yoke arms and bars, and means operatively interposed between one o f said bars and the adjacent bearing .device for moving the latter toward the opposed bearing device and for maintaining 1t in position for cooperating with said wrist pin, each of' said bearing devices involvingr ia plurality of detachably connected members embracing Said yoke arms between them.l 4. A pitman for operatively connecting the Wrist pin and walking beam of a drilling rig, said pitmen embodying a yoke, a plurality of relatively movable wrist pin bearing devices mounted in said yoke, and toggle Ameans for moving one of said bearing View with respect to the other, said mea-ns involving a bent lever, an integral link b1- furcated to receive said'lever and pivotally connected to said lever and to the adjacent bearing device, and a clevis bolt whose head vreceives said lever and is lpivotally connected thereto, said bolt and yo connected. Y

5. A pitman for operatively connecting the wrist pin` and walking beam of a drillin rig, said pitman embodying a yoke, a plura ity of re devices mounted within the yoke and adapted to receive the wrist pin between them, each yof said devices involving a recessed block having oppositely extendin flanges overlapping said yoke, me detac ably se-v cured to said -block and overlapping said yoke for retaining said block in assembled; relation to said yoke, and a wrist pin beare being adjustably ling member removably mounted on said,

block and extendin in to the recess of the latter, and releasab e means operatively interposed between said yoke and one of said bearing devices vfor maintaining the latter in operative relation to said wrist pin.

6. A pitman forl operatively connecting .the wrist pin and walking beam of a rig, said itman embodying a yoke, a plurality of re atively movable wrist pin bearingv devices mountedwithin thejyoke and adaptatively movable wrist pin bearing v izo ed to receive the wrist pin between them,

each of said devices involving a recessed block provided with oppositely extending members overlapping said yoke, means or retaining said block in assembled relation to said-yoke, and a removable Wrist pin bearing member fitting into the recess of said block,

' spring means being adapted to cause a separation of said bearing devices to release said wrist pin.

7. A Pitman for operatively connecting the'wrlst pin Vand walking beam of a drilling v rig, said Pitman embodying a yoke having opposi' ly disposed arms, a plurality of relativelymovable wrist pin bearing devices mounted between the arms of said yoke and adapted to receive the wrist pin between them, and releasable means for moving one of said devices with respectl to the other so as to cause it to assume and be maintained in operative relation to said Wrist pin, each of said bearing devices involving a block having oppositely projecting portions respectively overlapping said yoke arms, detachable means overlapping said voke arms for retaining vsaid block in assembled relation to said yoke, and a wrist pin bearing lmember removably mounted on said block and extending into the recess of the latter, said block having a portion projecting hetween said bearing member and said detachable means and serving to relieve said detachable means from radial thrust imposed on said bearing member by the wrist pin.

In testimony whereof I aiiix my signature.

vLinens PETTIGREW NEILsoN, sR. 

